An actuator and a tactile sensation providing apparatus that can reduce the number of elements are provided. The actuator includes a piezoelectric element and a diaphragm that has the piezoelectric element attached thereto and vibrates according to an expanding and contracting displacement of the piezoelectric element. The diaphragm converts the expanding and contracting displacement of the piezoelectric element into a vibration in a predetermined direction. The diaphragm supports a vibration object for providing a tactile sensation, in a displaceable manner.